One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Oak Forest can be used to determine when you can plant catharanthus.

Planting Calendar for Catharanthus

Frost tolerance for catharanthus:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably not a good idea to plant catharanthus until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant catharanthus in Oak Forest is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant catharanthus and expect a good harvest is probably August. If you wait any later than that and your catharanthus may not have a chance to grow to maturity. Starting your catharanthus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Oak Forest the average date of last frost happens on April 15. You can expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Oak Forest and it changes from year to year. Half of the time in Oak Forest you get a frost after April 15 so just be sure to be ready to protect your catharanthus if you have one of those late frosts.

USDA Zone Info for Oak Forest

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Oak Forest

You may be interested in your other planting guides for Oak Forest.